The present invention relates to a device for preparing a liquid beverage from a cartridge. In particular, the invention relates to the preparation of hot or cold drinks from cartridges containing one or more food ingredients.
Numerous types of system for preparing drinks from cartridges exist. The way in which the cartridge is inserted into the machine preferably needs to be fairly direct, free of complications, and allow the cartridge to be moved easily after use.
The problem with some systems comprising cartridge support means incorporated into the machine stems from the fact that it is difficult to prevent any contact between the drink and the machine. These systems are ill-suited to multi-drink use because of the frequent contact between the drink and the cartridge support means. This then presents problems of cross-contamination and of hygiene, particularly with certain ingredients, such as milk.
Some systems therefore exist which comprise a removable cartridge holder, that is to say a cartridge holder that can be detached from the remainder of the device in order to solve these problems. Another advantage of this is that the cartridge can be disposed of more easily, particularly when it remains full of liquid after extraction. This then prevents cartridges that still contain liquid from being stored in the machine. It also makes the cartridge easier to replace and therefore makes it easier to rinse or clean the cartridge holder, for example, in a dishwasher.
Patent application WO 2006/082064 describes a device with a removable cartridge holder comprising an injector. The injector can be positioned at various locations relative to the surface of the cartridge and this makes it possible to optimize the flow of fluid within the cartridge and thus, for example, encourage the dissolving or dispersion of certain ingredients. A system such as this is still relatively complicated, however, and requires a good fit between the fluid unit of the machine and the injector belonging to the cartridge holder at the time of connection. The accuracy of the fit is awkward to achieve and may be adversely affected over the course of use of the system. The system may also present a problem that, when the cartridge is pressurized, delamination may arise in the region where the membrane that forms the injection surface is sealed against the edges of the body of the cartridge. A phenomenon such as this may be associated with the lack of clamping of the sealed joint by the injector support connected on the cartridge holder side where the clamping forces transferred by the support onto the edges of the cartridge are lower.
The other existing devices are unable to solve all the problems raised in relation to patent application WO 2006/082064.
Patent application EP 1 153 561 A1 relates to a device with a movable drawer and an injection unit which is lowered in a combined rotational and translational movement. The device comprises a single central piercing element and there is no choice as to where the piercing element is positioned. The cartridge support is able to move translationally but is not detachable from the device and therefore entails manipulation or an ejection system in order to allow the cartridge to be removed.
US patent application 2003/066431 relates to a coffee machine with a movable drawer. The movable drawer is not detachable here either. The injection unit may be a pivoting support comprising an injection spike which is folded down onto the top of the cartridge. However, the device does not anticipate sealed clamping between the cartridge and the injection unit which would allow high extraction pressures to be applied to the cartridge. A machine such as this is therefore essentially designed for low-pressure percolation use.
U.S. Pat. No. 3,260,190 relates to a coffee machine using cans comprising a detachable drawer which is inserted by sliding along rails. A system of levers allows the can-piercing means to be brought closer and engaged. These piercing means lock the can in the operating position.
Patent application WO 97/43937 relates to a removable adapter to accept a measured dose of coffee which is inserted under a hot water distributor by means of a bayonet-type rotary system in a sealed configuration.
Patent application US 2003/0071056 relates to a machine for dispensing drinks comprising a drawer into which there is fitted a can which is pierced by a movable injector, at the same time sealing directly around the can.
Patent application EP 1477092 relates to an appliance for dispensing drinks which comprises a drawer intended to accept a single serving pack for preparing a drink, which pack is slid into an operating position and secured in this operating position by locking means activated by the pressure exerted by the drawer at the time of insertion and which are situated at the end of the drawer.
Patent application EP 1 486 150 A2 relates to an appliance for dispensing drinks at low pressure comprising a drawer able to move in an injection unit in order to accept a can and associated with a can-ejection device. The injection unit comprises an injector able to move linearly and which is lowered to pierce the can. The drawer is immobilized by retaining means transversely locking it in order simply to prevent it from being removed. In the case of high internal pressures there is a risk of delamination along the sealing edges of the cartridge, because of the lack of clamping.
Patent application WO 2006/066624 relates to an appliance for preparing drinks from a pack comprising a pack support comprising an opening to accept the pack and a cover element to close the opening; closure means being provided and designed to move the pack support in a translational direction from a position in which the opening in the support is open into a position in which this opening is closed; the support being moved more particularly upwards by gear and crank means.
Most of the devices of the prior art are ill-suited to withstanding high pressures. Some devices which may be suited to high pressure still run into difficulties with sealing, lack of clamping, and mechanical complexity, these difficulties being associated with the need to produce a joint with the injection system which is both sealed and clamped firmly enough that it avoids any accidental removal of the cartridge holder or alternatively avoids any accidental delamination of the cartridge. The problem of high-pressure delamination may lead to steam or boiling water being splashed, or may even cause the cartridge to burst.
What is more, in most of the systems of the prior art, the cartridge is held clamped in the device usually by compression of the sealing means. In order to avoid any risk of accidental removal of the cartridge support, particularly where this is detachable, during the pressurizing mode, it is essential that this be clamped firmly enough in the device. Firm clamping on the sealing means itself may cause the cartridge to become crushed if the clamping is applied to the cartridge itself, or alternatively may cause fairly rapid deterioration of the sealing means and therefore of the sealing conditions. Another problem is that the injection fluid may partially cover the external surface of the cartridge if sealing is performed around the edges of the cartridge, and this is not very hygienic.